Total path length of race = 50 km
Time taken to complete the race = 5 hour 5 min 39 s
total time is given as = (5 * 60 * 60) + (5 * 60) + 39 s
[tex]T = 18339 s[/tex]
now we know that speed is given as ratio of distance and time
[tex]v = \frac{distance}{time}[/tex]
[tex]v = \frac{50* 1000}{18339}[/tex]
[tex]v = \frac{50000}{18339}[/tex]
[tex]v = 2.73 m/s[/tex]
So the speed for the above motion is 2.73 m/s